Help with locking rear wheel / Hayes HFX-9 XC

I have an issue with my Hayes HFX-9 XC brakes on the rear of my bike. When I am going downhill I cannot use the rears without locking them up. For obvious reasons I do not want this to happen.

Is there an adjustment I can make to help this? Different pads? The ones on there now are stock (and fairly new). I will even go as far as replacing the caliper if that is the concensus (no holy wars please). Bottom line is, I am nervous on any bigger downhills because I cannot control my speed correctly. fronts are fine but they are shimano xtr's.

Thanks for help/opinions.

To see what is right, and not to do it, is want of courage or of principle. -- Confucius
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Come join me at the Swamp

Basically, there is no adjustment. Try changing the pads and clean the rotor thoroughly with alcohol. I have the same brakes and don't have the problem with them locking up. Are the pads in there correctly?

Other factors can be tires ( pressure, tread and mounting direction), body position and balance of front and rear brake use.

OK makes sense. Would more pressure in a tire contribute to lockup or less?

Just for reference on the downhills I am talking about my ass is most definatly over the rear tire. I am using a panaracer fire XC mounted as rear with 38LBS of pressure. I also use very little if any of the front. I am also heavy if that matters (240LBS).

Thanks for the help guys. Somtimes as a noob you need the experience of others to push you in the right direction. Also to help you know the difference between **** and shinola. This board has been great for that.

To see what is right, and not to do it, is want of courage or of principle. -- Confucius
-----------------------------------------------------------------------------------
Come join me at the Swamp

OK makes sense. Would more pressure in a tire contribute to lockup or less?

Could be either. You have to experiment.

Just for reference on the downhills I am talking about my ass is most definatly over the rear tire. I am using a panaracer fire XC mounted as rear with 38LBS of pressure. I also use very little if any of the front. I am also heavy if that matters (240LBS).

Thanks for the help guys. Somtimes as a noob you need the experience of others to push you in the right direction. Also to help you know the difference between **** and shinola. This board has been great for that.

The Fire XC could be too small for your weight. Also if you have it mounted in the "rear" direction it will have less braking traction than if in the "front" direction.